Siege of Marienburg
1454 CE.
Shown on the map at 54.033°, 19.033°.
Siege of Marienburg occurred during the Thirteen Years' War between the Teutonic Knights and the Kingdom of Poland. Marienburg was the capital of the state of the Teutonic Order, in particular, the residence of the Grand Master of the order. An alliance of Prussians and Poles besieged the city beginning 27 February 1454 with mercenaries from Danzig (Gdańsk), and the necessary artillery.
Text from the Wikipedia article Siege of Marienburg (1454), licensed CC BY-SA 4.0.